From: Christoph Hellwig <hch@lst.de>

Date: Tue, 5 Sep 2017 18:46:47 +0200

Subject: [PATCH] ahci: don't use MSI for devices with the silly Intel NVMe

 remapping scheme

References: bnc#1060662

Patch-mainline: v4.12.12

Git-commit: f723fa4e69920f6a5dd5fa0d10ce90e2f14d189c

commit f723fa4e69920f6a5dd5fa0d10ce90e2f14d189c upstream.

Intel AHCI controllers that also hide NVMe devices in their bar

can't use MSI interrupts, so disable them.

Reported-by: John Loy <john.robert.loy@gmail.com>

Tested-by: John Loy <john.robert.loy@gmail.com>

Signed-off-by: Christoph Hellwig <hch@lst.de>

Fixes: d684a90d38e2 ("ahci: per-port msix support")

Signed-off-by: Tejun Heo <tj@kernel.org>

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Jiri Slaby <jslaby@suse.cz>

---

 drivers/ata/ahci.c | 9 ++++++++-

 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c

index c69954023c2e..13080f1284e8 100644

--- a/drivers/ata/ahci.c

+++ b/drivers/ata/ahci.c

@@ -1467,7 +1467,14 @@ static void ahci_remap_check(struct pci_dev *pdev, int bar,

 		return;

 	dev_warn(&pdev->dev, "Found %d remapped NVMe devices.\n", count);

-	dev_warn(&pdev->dev, "Switch your BIOS from RAID to AHCI mode to use them.\n");

+	dev_warn(&pdev->dev,

+		 "Switch your BIOS from RAID to AHCI mode to use them.\n");

+

+	/*

+	 * Don't rely on the msi-x capability in the remap case,

+	 * share the legacy interrupt across ahci and remapped devices.

+	 */

+	hpriv->flags |= AHCI_HFLAG_NO_MSI;

 }

 static int ahci_get_irq_vector(struct ata_host *host, int port)

-- 

2.14.2